Born for Adversity
by REwrites24
Summary: Few people knew just how much Sirius loved Regulus, all they really saw were two brothers always at odds. One-shot. Blackcest. RB/SB and mentions of RL/SB.


**Title:** Born for Adversity

**Summary:** Few people knew just how much Sirius loved Regulus, all they really saw were two brothers always at odds. One-shot. Blackcest. SB/RB and mentions of SB/RL. Please read the warnings!

**Warnings:** Incest, sex between minors, language.

**Disclaimer: **Harry Potter and all related characters belong to JK Rowling. No copyright infringement is intended and no profit is being made.

**Notes:** Not beta'd. This was begging me to write it. If you do not like Blackcest please do not read.

* * *

**Born for Adversity**

_"A friend loveth at all times, and a brother is born for adversity." - Proverbs_

oOo

"Sirius, this is stupid. I don't want to play anymore." A seven year old Regulus Black stood, arms crossed, and tossed his head haughtily like he'd seen his mother do countless times.

Sirius rolled his eyes and made an impatient noise. "Would you rather go back down stairs and play with Bella or Cissa?" he asked. It was almost a threat.

"No," Regulus said hastily. Bella's and Cissa's idea of fun was to put ribbons in his hair and makeup on his face. Sirius teased him for a whole day until he admitted to a tearful Regulus that they used to do the same thing to him.

"It's loads more fun and they get sick of it much quicker if you just play along. Especially when you strut around the room and tell them you make a much prettier girl than either of them," Sirius had explained.

"But, Sirius, playing house is dumb."

"Nonsense, you've seen the way mum hexes Father when she's angry. It will be fun. Now, I expect a proper greeting when I arrive home from business," he said importantly in his best impression of Orion Black. Regulus giggled but Sirius did not break character, even going so far as to arch one elegant eyebrow imperiously.

"Welcome home, Mr. Black," he said with a curtsey and they both tried hard to keep their lips from twitching.

"No kiss?" Sirius asked in mock outrage. Regulus had to cover his mouth to keep from giggling again. Their mother and father never kissed. He would wonder years later how the two cold people he called parents ever came together to produce two children.

"I'm waiting," Sirius said impatiently, tapping his foot, his arms crossed.

Feeling suddenly shy, Regulus leaned forward and placed a quick kiss on his brother's lips. "Welcome home, Sirius."

"Bloody girl!" Sirius teased and he tackled Regulus to the ground, his fingers instantly at his sides, tickling him mercilessly.

"No, Sirius! Stop!" he shrieked between bouts of laughter, his brother planted firmly in his lap. He could hardly breathe for laughing as he grappled at his brother's hands in effort to thwart him. He managed to get a solid pinch in the soft fabric covering the boy's stomach. Sirius gave a rather undignified squeal and toppled off.

"You're a nutter," Regulus said a little breathlessly, poking Sirius again in the side.

"You love me," Sirius intoned with certainty, giving his head a fond pat. "Come on." He rose to his feet and held out a hand to help Regulus up. "House _is_ dumb. Let's go put ink in Bella's tea."

* * *

oOo

* * *

Thunder cracked loudly outside making the windows rattle in their frames. Sirius lay awake, flat on his back, his arms behind his head, counting down from ten.

_Ten…nine…eight…seven…_

Boom!

Another rattle. This one much closer.

_Ten…nine…eight…_

And there is was. The soft snick of his door opening and closing and a gasp as the thunder boomed once more. Hurried footsteps and a quick jab at his leg.

"Sirius, are you awake?"

"No."

More thunder and a flash of blue lightning through the curtains. Regulus yelped and dove under the covers as Sirius held them up for him.

"Budge over," Regulus ordered, poking him again.

"You're in _my_ bed, you don't call the shots," but he scooted over anyway.

Regulus snuggled close, resting his head on Sirius's shoulder, and Sirius smiled to himself. They rarely indulged in such intimacies any more. The disapproving glare over brotherly affection their mother gave them was enough to forestall any physical contact that was not completely proper.

"You are far too old to be acting that way," she scolded Regulus one day. "Do not encourage him Sirius."

Sirius curled his arm around a bony shoulder defiantly. The storm outside raged on, growing dimmer with each passing minute.

"Are you very excited you'll be leaving for Hogwarts soon?" Regulus whispered, his warm breath ghosting over Sirius's neck.

"Are you mad? Of course I'm excited. I can't wait."

Regulus was quiet for a long time. "I bet you'll be having loads of fun while I'm stuck here with no one but Kreacher for company," he said and there was a touch of bitterness in his voice. Sirius winced as he realized how his words might have been interpreted.

"It's only for a year, Reg. Next year you'll join me and we'll take the school by storm."

"We'll be the Kings of Slytherin," Regulus agreed with a boyish giggle.

"I'll be the King, what with me being so much older and wiser. You'll be the Prince." He gave the bony shoulder a pat. Silence fell once more. The storm was nothing more than a gentle growl by that point.

"I'm going to miss you."

"I'll miss you too, mate."

Sirius placed a kiss on the boy's cheek which was promptly wiped away with a disgruntled "gross." He snorted and burrowed further into his pillow, Regulus's head still cradled on his shoulder. "Make sure you're back in your own bed before Kreacher comes to fetch us for breakfast."

* * *

oOo

* * *

"Damn it, Regulus, did you steal my fucking shirt again? Stupid bitch Bella," Sirius stormed as he entered Regulus's room, his shirt unbuttoned and covered in what looked like wine.

Regulus sat bolt upright on his bed, the hand fisting his cock stilling. Surprised grey eyes met his own. His brother's mouth dropped in shock then split into a wide grin. Sirius fell into the door laughing hysterically as he clutched his sides. Regulus felt his whole body grow warm.

"I'm not feeling well." Sirius mocked his earlier words with a high-pitched whine. "I'll just have a quick lie down."

"Shut up, Sirius!"

"Did Auntie Dorea do it for you? Do you like the way she smacked your bottom and said you were too skinny?"

"Ugh!" Regulus removed the hand between his legs as if he'd been burned. Sirius collapsed into a fit of giggles again. "Get out!"

Sirius recovered enough to stand. "Honestly, Reg, I've been living with three other blokes for five years. Nothing I haven't seen before," he mused and proceeded to search for his missing shirt, shrugging the ruined one to the floor, a snort of laughter escaping every so often.

Regulus pulled the blanket up to cover himself as he watched his brother move, shirtless, around the room. "Ah ha, you little thief!"

Regulus watch in fascination as the muscles in his brother's back flexed as he pulled the shirt on. His cock gave an involuntary twitch.

"Enjoying the view?" Sirius asked when he turned around to catch Regulus staring. He got a brief glimpse of bare chest as Sirius buttoned the shirt with swift, nimble fingers. Regulus looked away mortified. Sirius leaned against the post of his bed casually.

"Will you get out already? I'd quite like to finish."

"Have you ever thought of touching another boy?" Sirius asked curiously.

Regulus stared. "O-of course not!"

"I have. Done more than think about it, actually."

"With who? That twat Potter?"

"Nope."

"You can't possibly have done it with that Pettigrew fellow; that would be positively revolting. Your half-breed friend, was it? Lupin?"

"Shut up about Remus!" Sirius warned, switching to a much more aggressive stance.

Regulus smirked. "Not defending Pettigrew's honor I see. Lupin then. Had your pretty little hands all over his Mudblood cock did you?"

Sirius grabbed him by the collar bringing their faces close. "One more word, Regulus, and I'm going to beat you to a bloody pulp."

Regulus was baffled at how considerably the way his excitement grew as Sirius manhandled him. Merlin, he needed to come. Badly. "Really, Sirius? Beat me?" he smiled at the innuendo.

"You'd like that wouldn't you?" Sirius returned, his voice taking on a teasing quality. Before he realized what was happening, Sirius placed himself on the bed behind Regulus, his back against the headboard.

"What are you doing?" Regulus panicked. He'd only meant to give a little back for the embarrassment of getting caught wanking. Sirius gave a nasty snicker.

"Giving you what you want, of course."

He felt Sirius grab him by the hips and haul him back so he was seated neatly between his brother's legs. There was the beginning of an unmistakable erection pressing into the small of his back.

"Sirius, stop!" he said quickly as a hand weaved its way beneath his arm to reach between his legs. The hand stopped to rest on his hip, tracing lazy circles on the exposed skin there. Unbidden, his hips gave a little trust at the intimate contact. Sirius laughed against his neck, warm breath tickling his ear. He bit his lip to prevent a moan from escaping.

"You want this."

"I don't," he protested as the hand on his hip made bolder advances.

"Are you backing out?" Sirius asked and the teasing sultry tone was gone.

Sirius would always ask him that when he thought Regulus was being a baby about a prank they were pulling. "Just go away, Reg, I'll do it alone."

Taking his hesitance as permission to continue, Sirius ran a thumb over the slit of his cock, smoothing the bead of fluid across the head. Regulus actually moaned that time and he felt a brush of lips on the pulse of his neck.

"Still want me to stop?" Sirius asked in his ear, and Regulus felt teeth lightly graze the skin there causing a pulse of white hot pleasure to course through him. He could only shake his head. No. He would, quite possibly, kill Sirius if he stopped.

Regulus was panting as his brother skillfully stroked him; long, slow, agonizingly wonderful strokes that were making his head spin and his toes curl. He cried out softly when Sirius flicked his wrist just so. "Oh!"

"You like that?"

Regulus nodded and bucked his hips into the fist, needing more, needing Sirius to go faster because he was so close.

"Say it."

"Yes."

"Yes what?"

"Yes I bloody well like it."

Sirius bit sharply on his shoulder and flicked his wrist expertly twice more and Regulus was coming harder than he'd ever come in his entire life. His eyes flew wide open, but he could hardly see for the white spots that clouded his vision as his orgasm was torn from his body. He leaned back into his brother's arms, breathing heavily as Sirius pulled every last drop from him.

His head was still spinning when he realized Sirius was thrusting lightly against his back, his erection pressed firmly between them. "Fuck, Reg, move," Sirius growled, giving him a more instant nudge with his hips.

Regulus scrambled forward until he was seated at the end of the bed. He watched, fascinated, as Sirius single-handedly flipped open the clasp on his trousers and pushed them down his hips until his cock sprang free.

He waited for Sirius to tell him to fuck off but his brother just dropped him a wink behind his long fringe as he began to stroke himself, his hand still wet with Regulus's come. He noted, distractedly, that Sirius looked different. Thicker and longer and with more hair, but that was to be expected, right? He was more than a year older after all.

The pulsing between his legs surprised him, given the way he'd come not minutes ago. Almost automatically, his hand went to his slowly stiffening cock. He tried to copy the way Sirius did it, running his thumb over the head and twisting his wrist just so. Fuck it was good.

Sirius was panting and gave a lusty moan. White teeth shone as he bit down on his lip, his eyes dark and locked with Regulus. Bloody show off. Sirius always did love to be the center of attention.

They matched each other, stroke for stroke, increasing in speed. He was fully hard again by the time Sirius began moaning in earnest, his hips thrusting erratically into each pass of his hand across the steadily leaking head of his swollen cock. Regulus watched as his brother's eyes fluttered closed; his brow knitted, and then flew widely open as he began crying out, "Fuck, oh, fuck!"

Sirius clutched the sheets tightly with his free hand, hips lifting clear off the bed. White ejaculate spilled over his fingers in jerky spurts as he continued to cry out his release. Watching his proud, confident brother come unraveled was all it took to push Regulus over the edge once more. Sirius leaned back on the headboard, his chest heaving as Regulus slumped onto his side, curling contentedly on the bed.

"Damn it. I need another shirt now," Sirius said after several minutes and they both dissolved into laughter. Sirius removed his shirt and used it to clean himself off and tossed it to Regulus.

He wrinkled his nose and, taking a clean edge of the shirt between his thumb and forefinger, deposited the shirt on the floor. He reached for his wand. "Really, Sirius, you can be such a pleb sometimes," he said as he cast a cleaning charm on himself.

* * *

oOo

* * *

Regulus hated Remus Lupin. Hated him, quite a lot actually, which was unusual for him. Unlike Sirius, who would happily nurse a grudge with his dying breath, Regulus felt the energy spent hating someone was much better put to use by exacting calculated revenge. But he could afford to make an exception for Lupin.

He wasn't even very good looking. Rather ordinary really, very thin with brown hair and brown eyes. He looked perpetually tired and pale. Regulus didn't know what Sirius saw in him. He glowered at the boy as he sat much too close to his brother across the hall during dinner, smiling mysteriously at something Sirius was whispering in his ear.

Yes he definitely hated Remus Lupin, thinking he'd very much like to smack that smile off his face. If it were not for Lupin, Sirius would not have left home the previous summer. He thought back to the blazing row between his mother and Sirius that culminated in Sirius's departure.

"_You're mental!" Sirius screamed at his mother, his face contorted in rage. "I'm not marrying some pureblooded tart! I don't give a damn about continuing the family name!"_

"_How dare you speak to me that way you ungrateful brat! You have a duty to this family, it is time you started taking it more seriously!"_

"_FUCK this family! I don't care! Aren't you listening? I. DON'T. CARE!"_

_Regulus winced as he a heard the sound of a hard smack and then deadly silence. He peeked over the banister from his secret listening place. His mother was glaring at her elder son, her eyes truly terrifying. Sirius's head was bent, his long hair falling into his face, his shoulders shaking and for a wild moment Regulus though he might be crying until he heard the sound of laughter. Sirius threw back his head cackling madly and sounding quite deranged._

"_Stop laughing this instant!" Sirius continued to laugh and he pushed roughly past their mother, making his way to the stairs. "I did not give you permission to leave."_

"_Fuck your permission! I'm done. Cancel your parties because I'll not be attending. There isn't a pureblooded witch on this world I would marry so don't bother parading them around for me. If you come across a good-looking bloke though, send him my way."_

"_What did you just say?" she asked, her voice carrying a dangerous tone that usually meant she was about to explode with rage._

"_You heard me."_

"_I will not tolerate that sort of perversion under this roof! You have been nothing but an embarrassment for years now! Making friends with half-bloods and blood-traitor scum! Strutting around this house like a proud little Gryffindor! I will not stand for it any longer, Sirius!"_

"_Good! Neither shall I!" _

"_Get back here!"_

_But Sirius ignored her as he ascended the stairs, two at a time, moving past Regulus without even sparing him a glance. Regulus followed and leaned against the door as he watched Sirius kick his trunk open and begin throwing things inside it violently._

"_What are you doing?"_

_Sirius looked up and scowled. "I'm leaving. I've had enough."_

"_You can't leave."_

"_What do you care? You're the good son."_

Regulus watched his brother leave their home without a backward glance that night. As far as he was concerned it was Remus Lupin's fault. Sirius was never a queer until he and Lupin got together.

Not only did he lose his brother that night he also lost his one source of entertainment while at home. Since the first time Sirius placed his hands on him Regulus had become quite addicted to his touch. He did not think of himself as queer, not like Sirius. They'd always been close, after all, and it was a much more enjoyable way of getting off than on his own.

He watched Lupin rise from his seat and leave the hall alone. Sirius's eyes followed the boy and he sat for another minute or two then left the hall himself. Regulus was on his feet and exiting the hall before he'd even made the conscious decision to follow. He walked in the direction he saw Sirius go and heard low voices in corridor to his right after several minutes.

"Not now, Sirius."

"But, Moony."

"Later—ah—we'll have the dorm to ourselves tonight."

Regulus hid himself behind a suit of armor as he heard the unmistakable sounds of kissing. There was a giggle and moan and Regulus entertained the idea of kicking the suit of armor over to give the two boys a fright.

"Pads…I have to go."

"Fine, go be a good little Prefect." Sirius sounded like he was pouting.

"I'll see you later."

He stepped out from his hiding place when Sirius walked by, alone. "Lupin playing hard to get?" he asked and Sirius spun around, a dark glower already on his face.

"Go away, Regulus."

"What does he let you do to him, hmm? Do you actually fuck him? Is it different fucking a Mudblood for a change?"

Sirius had his hands around his throat in an instant, pinning him to the stone wall behind him. Regulus felt his body react immediately as Sirius brought his face close. "Never call him that again," Sirius hissed his voice low and dangerous.

Regulus knew he should not goad Sirius any further; he looked positively livid and Regulus did not fancy having his nose broken, but it had been absolute ages since Sirius touched him and the tight fingers on his throat and the warm press of their chests was making him dizzy with desire.

"Or what?" Sirius increased the pressure of his strangle, a low growl in his throat. "Mud…blood."

Sirius shook him roughly causing the back of his head to slam in the stone wall. Black spots swam before his eyes. He felt a thigh pressed between his legs and a deep chuckle in his ear as it made contact his rapidly stiffening dick. He couldn't stop the groan that escaped his lips as Sirius pressed harder against his arousal.

"Care to have a go?" Regulus managed to ask. "For old time's sake?"

Several minutes later, as he was biting his lip to keep from crying out, bent over a desk in a dark classroom, Sirius pounding into him with brutal force, Regulus thought there was no sweeter revenge than stealing Sirius back from Remus Lupin.

* * *

oOo

* * *

"Fucking hell! Reg?" he heard Sirius ask as the mask was ripped from his face. Regulus glared insolently back at his brother. Two years has changed Sirius considerably. He looked different, rougher. His eyes were hard as steel but Regulus thought he saw a flicker of something old and familiar in the grey depths and decided to press his advantage.

"Going to kill me, brother?" he asked, eyeing the wand pointed directly at his heart. Aurors had carte blanche when it came to the capture of Death Eaters these days. Sirius could kill him with impunity if he wanted to. "Mother would be heartbroken."

He felt the wand dig into the side of his throat. "Like I give a shit about that cunt. Merlin, Reg, what are you fucking doing with these people? Is this what you want? To be a killer? Answer me!"

"I don't want to be a killer," he said honestly. "I've been trying to get out for months but one doesn't exactly hand in their resignation to the Dark Lord."

"Let me help you."

"No. I have a plan, Sirius. Just let me go."

He could hear the sounds of shouting and duels raging on nearby. Sirius stared at him for a long moment. Regulus could see him debating with himself.

"If I bring you in you'll be out. We can protect you."

"No you can't. I'll be in a cell in Azkaban by morning. If they don't decide to kill me straight off. Thank your buddy Crouch for that."

"Fuck! Damn it I can't just walk away here, Reg!"

"I told you I have a plan."

The sounds of fighting grew closer. Sirius lowered his wand and grabbed him roughly by the front of his robes pulling him in for a fierce hug. Regulus returned the embrace, holding his brother tightly. He felt a kiss pressed to his temple. "Just don't get yourself killed."

* * *

oOo

* * *

"Let Kreacher drink it, Master!" the house-elf sobbed as he held Regulus upright. He was kneeling on the small island, violent tremors causing his body to shake. His vision swam as he fought off another hallucination. "Please, Master Regulus! Order Kreacher to drink it!"

"No, Kreacher. I am not going to order you to torture yourself. I have to do this."

He drank another cup full of potion, the foul liquid burning fresh fire as he swallowed. Kreacher continued to wait, tugging on his ears and Regulus tried to ignore him as the visions assaulted him once more.

_He was torturing a Muggle child, feeling like he might vomit as she screamed. _

_He was holding his mother's hand as she cried beside his father's deathbed._

_He was healing Kreacher—his oldest friend, since things with Sirius started going so foul—who was broken and crying. It was his fault. _

_He was watching his mother blast Sirius's name off the family tree._

Hot tears were spilling down his face as dozens of insults, curses, and punches traded with his brother surfaced. He tried to shake them off as Kreacher obediently fed him more potion. The visions were not even making much sense any more. He sobbed and screamed as random images and feelings of despair overcame him in rapid succession, the fire inside burning excruciatingly hot.

_Regulus crying himself to sleep the night Sirius left for Hogwarts._

_A hard slap across the face by his mother._

_Casting a Cruciatus as the Dark Lord smirked over his shoulder. _

_Watching Sirius fuck Remus Lupin in a dark classroom. "I love you, Remus."_

His head hit the stone surface of the island as he collapsed, breathing heavily, tears flowing freely. Kreacher was still wailing loudly. He was dying of thirst. He crawled to the edge slowly and reached over to bring a handful of water to his mouth.

"Master Regulus, no!" Kreacher shouted, but Regulus was already sipping water from his cupped hands. A scaly, dead hand grabbed him tightly by the wrist. Regulus managed to break away but the water began stirring as more bodies surfaced. Another hand grabbed his leg and began pulling him over the edge. He kicked violently and scrambled for his wand as more hands reached out pulling at his legs and robes.

Kreacher was crying out and tugged against the Inferi that were pulling Regulus into the water but there were too many of them and Regulus felt his body dip into the water. He clung to the edge with what little energy he had left.

"Take the locket and get out, Kreacher! You have to destroy it! Leave the fake one!"

"Kreacher cannot leave Master Regulus!"

"Do as I say!" He was pulled deeper. This was it. He was going to die. "Kreacher…don't tell Sirius."

* * *

oOo

* * *

Remus found Sirius in his brother's room. The house was dank and there were a great many terrifying things that were liable to take a healthy bite out of you if you weren't careful, but this room was still neat, if not a bit dusty. Sirius was seated on the bed his shoulders slumped as he ran a hand idly on the quilted comforter.

"I miss him, Remus."

"Of course you do. He was your brother, whatever happened between you two in the past."

He sat gently beside Sirius on the bed and placed a comforting hand on the man's boney back. Sirius leaned into the touch and he sighed.

"He wanted to get out. He said he had a plan. Why couldn't I help him, Remus?"

"You remember what it was like back then. We were lucky to walk away with our own lives, let alone save someone else's."

"I loved him."

"I know you did." He took Sirius in his arms holding his head against his chest as he shook with silent tears. Few people knew just how much Sirius loved Regulus, all they really saw were two brothers always at odds. He placed a kiss in dark, unkempt hair. "I know you did."

* * *

oOo

* * *

He was dead.

Fuck.

Fuck fuck fucking fuck!

He wanted to storm and rage and break something that made a nice loud noise as it shattered but there was nothing nearby. The world was soft, white emptiness. He pulled at his hair instead and was surprised to notice how short and smooth it felt. He looked at his hands which were no longer thin and brittle and ran them over his chest. It felt powerful and he couldn't feel a rib poking out at all.

This was not the wasted body given to him by Azkaban. He smiled. Perhaps death had its advantages.

He turned at the sound of footsteps approaching behind him. There was a dark figure walking towards him in the white swirling mist. Sirius waited, anticipation building somewhere in his stomach. His face split into a wide grin as Regulus emerged from the sea of white, a mischievous smirk on his face.

He stopped just in front of Sirius and leaned forward to place a soft kiss on his lips.

"Welcome home, Sirius."


End file.
